TY - JOUR
T1 - Performance Metrics for a Modern BOPP Capacitor Film
AU - Ritamäki, Mikael
AU - Rytöluoto, Ilkka
AU - Lahti, Kari
N1 - Funding Information:
This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 720858.
Publisher Copyright:
© 1994-2012 IEEE.
Copyright:
Copyright 2019 Elsevier B.V., All rights reserved.
PY - 2019/8/1
Y1 - 2019/8/1
N2 - In this paper, a set of performance metrics for modern biaxially oriented polypropylene (BOPP) capacitor films is established. The fundamental and applied properties of BOPP films required for application in state-of-the-art DC metallized film capacitors are reviewed, highlighting aspects related to high temperature operation, base PP properties and film processing. Commercial BOPP films — both base films and metallized films based on classic isotactic PP — are studied comprehensively, encompassing structural–morphological characterization and short- to medium-term dielectric characterization. Dielectric spectroscopy results demonstrate the negligible dielectric losses of BOPP, being in the range of 10– 4 or less in the expected operation temperature regime. Thermally stimulated depolarization current (TSDC) measurements indicated a modest density of shallow traps (~0.75 eV) and a high density of deep traps (~1.08 eV) in the 5 μm and 10 μm film variants showing differences presumably arising from film processing. Such an electronic structure was found to be connected with ultra-low conductivity (in the range of 10– 17 –10– 16 S/m), high breakdown strength (~700 V/μm) and negligible space charge accumulation up to temperatures of ~70 °C. It is shown that at current design stresses (~200 V/μm at ~60 °C) BOPP is operated close to its fundamental thermal and electrical limitations. Voltage endurance tests at higher fields revealed the onset of high-field degradation and drastically reduced insulation life, and thermal activation of deep traps in the high temperature region (~100 °C) was found to result in reduced dielectric performance.
AB - In this paper, a set of performance metrics for modern biaxially oriented polypropylene (BOPP) capacitor films is established. The fundamental and applied properties of BOPP films required for application in state-of-the-art DC metallized film capacitors are reviewed, highlighting aspects related to high temperature operation, base PP properties and film processing. Commercial BOPP films — both base films and metallized films based on classic isotactic PP — are studied comprehensively, encompassing structural–morphological characterization and short- to medium-term dielectric characterization. Dielectric spectroscopy results demonstrate the negligible dielectric losses of BOPP, being in the range of 10– 4 or less in the expected operation temperature regime. Thermally stimulated depolarization current (TSDC) measurements indicated a modest density of shallow traps (~0.75 eV) and a high density of deep traps (~1.08 eV) in the 5 μm and 10 μm film variants showing differences presumably arising from film processing. Such an electronic structure was found to be connected with ultra-low conductivity (in the range of 10– 17 –10– 16 S/m), high breakdown strength (~700 V/μm) and negligible space charge accumulation up to temperatures of ~70 °C. It is shown that at current design stresses (~200 V/μm at ~60 °C) BOPP is operated close to its fundamental thermal and electrical limitations. Voltage endurance tests at higher fields revealed the onset of high-field degradation and drastically reduced insulation life, and thermal activation of deep traps in the high temperature region (~100 °C) was found to result in reduced dielectric performance.
UR - http://www.scopus.com/inward/record.url?scp=85070479698&partnerID=8YFLogxK
U2 - 10.1109/TDEI.2019.007970
DO - 10.1109/TDEI.2019.007970
M3 - Article
SN - 1070-9878
VL - 26
SP - 1229
EP - 1237
JO - IEEE Transactions on Dielectrics and Electrical Insulation
JF - IEEE Transactions on Dielectrics and Electrical Insulation
IS - 4
ER -